Humboldt-Universität zu Berlin - Experimentelle Biophysik

Arend Vogt

Light-driven pumps have been intensively investigated over the last decades mainly by spectroscopic means and were recently employed in optogenetics for silencing of neuronal activity and for voltage sensing. Surprisingly, the knowledge about the electrophysiological properties of ion pumps in living cells is still poor. My work focusses on microbial pumps using two-microelectrode voltage-clamp measurements (TEVC) on Xenopus leavis oocytes. For example, the proteorhodopsin-like pump from cyanobacterium Gloeobacter violaceus (GR) is characterized by an inward directed proton flux at high electrochemical load, i.e. negative voltage and low pH (Vogt A and Wietek J, Hegemann P., 2013). Furthermore, subjects of my work are investigations of the gating mechanism of channelrhodopsins as well as color tuning facilitated by retinal analogs.

Publications:

1. Grimm, C., Silapetere, A., Vogt, A., Bernal Sierra, Y., Hegemann, P. 2018. Electrical properties, substrate specificity and optogenetic potential of the engineered light-driven sodium pump eKR2. Scientific reports 8: 9316. doi: 10.1038/s41598-018-27690-w

2. Vogt, A. 2017. Elektrophysiologische Untersuchung des gerichteten Protonentransportes in mikrobiellen Rhodopsinen. dissertation. doi: 10.18452/17713

3. Ferenczi, E.A., Vierock, J., Atsuta-Tsunoda, K., Tsunoda, S.P., Ramakrishnan, C., Gorini, C., Thompson, K., Lee, S.Y., Berndt, A., Perry, C., Minniberger, S., Vogt, A., Mattis, J., Prakash, R., Delp, S., Deisseroth, K., and Hegemann, P. 2016. Optogenetic approaches addressing extracellular modulation of neural excitability. Scientific reports 6: 23947. doi: 10.1038/srep23947

4. Vogt, A., Guo, Y., Tsunoda, S.P., Kateriya, S., Elstner, M., and Hegemann, P. 2015. Conversion of a light-driven proton pump into a light-gated ion channel. Scientific reports 5: 16450. doi: 10.1038/srep16450

5. AzimiHashemi, N. *, Erbguth, K. *, Vogt, A. *, Riemensperger, T., Rauch, E., Woodmansee, D., Nagpal, J., Brauner, M., Sheves, M., Fiala, A., Kattner, L., Trauner, D., Hegemann, P., Gottschalk, A., and Liewald, J.F. 2015. Synthetic retinal analogs modify the spectral and kinetic characteristics of microbial rhodopsin optogenetic tools. Nature communications 6: 6458. doi: 10.1038/ncomms7458

6. Wietek, J. *, Wiegert, J.S. *, Adeishvili, N., Schneider, F., Watanabe, H., Tsunoda, S.P., Vogt, A., Elstner, M., Oertner, T.G., and Hegemann, P. 2014. Conversion of channelrhodopsin into a light-gated chloride channel. Science 344(6182): 409-412. doi: 10.1126/science.1249375

7. Vogt, A. *, Wietek, J. *, and Hegemann, P. 2013. Gloeobacter rhodopsin, limitation of proton pumping at high electrochemical load. Biophysical journal 105(9): 2055-2063. doi: 10.1016/j.bpj.2013.08.031

*equal contribution